content: /* ===========================================================
   * JFreeChart : a free chart library for the Java(tm) platform
   * ===========================================================
   *
   * (C) Copyright 2000-2011, by Object Refinery Limited and Contributors.
   *
   * Project Info:  http://www.jfree.org/jfreechart/index.html
   *
   * This library is free software; you can redistribute it and/or modify it
   * under the terms of the GNU Lesser General Public License as published by
   * the Free Software Foundation; either version 2.1 of the License, or
   * (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
   * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
   * License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
   * USA.
   *
   * [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
   * Other names may be trademarks of their respective owners.]
   *
   * ---------
   * Week.java
   * ---------
   * (C) Copyright 2001-2008, by Object Refinery Limited and Contributors.
   *
   * Original Author:  David Gilbert (for Object Refinery Limited);
   * Contributor(s):   Aimin Han;
   *
   * Changes
   * -------
   * 11-Oct-2001 : Version 1 (DG);
   * 18-Dec-2001 : Changed order of parameters in constructor (DG);
   * 19-Dec-2001 : Added a new constructor as suggested by Paul English (DG);
   * 29-Jan-2002 : Worked on the parseWeek() method (DG);
   * 13-Feb-2002 : Fixed bug in Week(Date) constructor (DG);
   * 26-Feb-2002 : Changed getStart(), getMiddle() and getEnd() methods to
   *               evaluate with reference to a particular time zone (DG);
   * 05-Apr-2002 : Reinstated this class to the JCommon library (DG);
   * 24-Jun-2002 : Removed unnecessary main method (DG);
   * 10-Sep-2002 : Added getSerialIndex() method (DG);
   * 06-Oct-2002 : Fixed errors reported by Checkstyle (DG);
   * 18-Oct-2002 : Changed to observe 52 or 53 weeks per year, consistent with
   *               GregorianCalendar. Thanks to Aimin Han for the code (DG);
   * 02-Jan-2003 : Removed debug code (DG);
   * 13-Mar-2003 : Moved to com.jrefinery.data.time package, and implemented
   *               Serializable (DG);
   * 21-Oct-2003 : Added hashCode() method (DG);
   * 24-May-2004 : Modified getFirstMillisecond() and getLastMillisecond() to
   *               take account of firstDayOfWeek setting in Java's Calendar
   *               class (DG);
   * 30-Sep-2004 : Replaced getTime().getTime() with getTimeInMillis() (DG);
   * 04-Nov-2004 : Reverted change of 30-Sep-2004, because it won't work for
   *               JDK 1.3 (DG);
   * ------------- JFREECHART 1.0.x ---------------------------------------------
   * 06-Mar-2006 : Fix for bug 1448828, incorrect calculation of week and year
   *               for the first few days of some years (DG);
   * 05-Oct-2006 : Updated API docs (DG);
   * 06-Oct-2006 : Refactored to cache first and last millisecond values (DG);
   * 09-Jan-2007 : Fixed bug in next() (DG);
   * 28-Aug-2007 : Added new constructor to avoid problem in creating new
   *               instances (DG);
   * 19-Dec-2007 : Fixed bug in deprecated constructor (DG);
   * 16-Sep-2008 : Deprecated DEFAULT_TIME_ZONE (DG);
   *
   */
  
  package org.jfree.data.time;
  
  import java.io.Serializable;
  import java.util.Calendar;
  import java.util.Date;
  import java.util.Locale;
  import java.util.TimeZone;
  
  /**
   * A calendar week.  All years are considered to have 53 weeks, numbered from 1
   * to 53, although in many cases the 53rd week is empty.  Most of the time, the
   * 1st week of the year *begins* in the previous calendar year, but it always
   * finishes in the current year (this behaviour matches the workings of the
   * <code>GregorianCalendar</code> class).
   * <P>
   * This class is immutable, which is a requirement for all
   * {@link RegularTimePeriod} subclasses.
   */
  public class Week extends RegularTimePeriod implements Serializable {
  
      /** For serialization. */
      private static final long serialVersionUID = 1856387786939865061L;
  
      /** Constant for the first week in the year. */
      public static final int FIRST_WEEK_IN_YEAR = 1;
  
      /** Constant for the last week in the year. */
      public static final int LAST_WEEK_IN_YEAR = 53;
  
      /** The year in which the week falls. */
      private short year;
  
      /** The week (1-53). */
      private byte week;
  
      /** The first millisecond. */
      private long firstMillisecond;
  
      /** The last millisecond. */
      private long lastMillisecond;
  
      /**
       * Creates a new time period for the week in which the current system
       * date/time falls.
       */
      public Week() {
          this(new Date());
      }
  
      /**
       * Creates a time period representing the week in the specified year.
       *
       * @param week  the week (1 to 53).
       * @param year  the year (1900 to 9999).
       */
      public Week(int week, int year) {
          if ((week < FIRST_WEEK_IN_YEAR) && (week > LAST_WEEK_IN_YEAR)) {
              throw new IllegalArgumentException(
                      "The 'week' argument must be in the range 1 - 53.");
          }
          this.week = (byte) week;
          this.year = (short) year;
          peg(Calendar.getInstance());
      }
  
      /**
       * Creates a time period representing the week in the specified year.
       *
       * @param week  the week (1 to 53).
       * @param year  the year (1900 to 9999).
       */
      public Week(int week, Year year) {
          if ((week < FIRST_WEEK_IN_YEAR) && (week > LAST_WEEK_IN_YEAR)) {
              throw new IllegalArgumentException(
                      "The 'week' argument must be in the range 1 - 53.");
          }
          this.week = (byte) week;
          this.year = (short) year.getYear();
          peg(Calendar.getInstance());
     }
  
      /**
       * Creates a time period for the week in which the specified date/time
       * falls, using the default time zone and locale (the locale can affect the
       * day-of-the-week that marks the beginning of the week, as well as the
       * minimal number of days in the first week of the year).
       *
       * @param time  the time (<code>null</code> not permitted).
       *
       * @see #Week(Date, TimeZone, Locale)
       */
      public Week(Date time) {
          // defer argument checking...
          this(time, TimeZone.getDefault(), Locale.getDefault());
      }
  
      /**
       * Creates a time period for the week in which the specified date/time
       * falls, calculated relative to the specified time zone.
       *
       * @param time  the date/time (<code>null</code> not permitted).
       * @param zone  the time zone (<code>null</code> not permitted).
       * @param locale  the locale (<code>null</code> not permitted).
       *
       * @since 1.0.7
       */
      public Week(Date time, TimeZone zone, Locale locale) {
          if (time == null) {
              throw new IllegalArgumentException("Null 'time' argument.");
          }
          if (zone == null) {
              throw new IllegalArgumentException("Null 'zone' argument.");
          }
          if (locale == null) {
              throw new IllegalArgumentException("Null 'locale' argument.");
          }
          Calendar calendar = Calendar.getInstance(zone, locale);
          calendar.setTime(time);
  
          // sometimes the last few days of the year are considered to fall in
          // the *first* week of the following year.  Refer to the Javadocs for
          // GregorianCalendar.
          int tempWeek = calendar.get(Calendar.WEEK_OF_YEAR);
          if (tempWeek == 1
                  && calendar.get(Calendar.MONTH) == Calendar.DECEMBER) {
              this.week = 1;
              this.year = (short) (calendar.get(Calendar.YEAR) + 1);
          }
          else {
              this.week = (byte) Math.min(tempWeek, LAST_WEEK_IN_YEAR);
              int yyyy = calendar.get(Calendar.YEAR);
              // alternatively, sometimes the first few days of the year are
              // considered to fall in the *last* week of the previous year...
              if (calendar.get(Calendar.MONTH) == Calendar.JANUARY
                      && this.week >= 52) {
                  yyyy--;
              }
              this.year = (short) yyyy;
          }
          peg(calendar);
      }
  
      /**
       * Returns the year in which the week falls.
       *
       * @return The year (never <code>null</code>).
       */
      public Year getYear() {
          return new Year(this.year);
      }
  
      /**
       * Returns the year in which the week falls, as an integer value.
       *
       * @return The year.
       */
      public int getYearValue() {
          return this.year;
      }
  
      /**
       * Returns the week.
       *
       * @return The week.
       */
      public int getWeek() {
          return this.week;
      }
  
      /**
       * Returns the first millisecond of the week.  This will be determined
       * relative to the time zone specified in the constructor, or in the
       * calendar instance passed in the most recent call to the
       * {@link #peg(Calendar)} method.
       *
       * @return The first millisecond of the week.
       *
       * @see #getLastMillisecond()
       */
      @Override
      public long getFirstMillisecond() {
          return this.firstMillisecond;
      }
  
      /**
       * Returns the last millisecond of the week.  This will be
       * determined relative to the time zone specified in the constructor, or
       * in the calendar instance passed in the most recent call to the
       * {@link #peg(Calendar)} method.
       *
       * @return The last millisecond of the week.
       *
       * @see #getFirstMillisecond()
       */
      @Override
      public long getLastMillisecond() {
          return this.lastMillisecond;
      }
  
      /**
       * Recalculates the start date/time and end date/time for this time period
       * relative to the supplied calendar (which incorporates a time zone).
       *
       * @param calendar  the calendar (<code>null</code> not permitted).
       *
       * @since 1.0.3
       */
      @Override
      public void peg(Calendar calendar) {
          this.firstMillisecond = getFirstMillisecond(calendar);
          this.lastMillisecond = getLastMillisecond(calendar);
      }
  
      /**
       * Returns the week preceding this one.  This method will return
       * <code>null</code> for some lower limit on the range of weeks (currently
       * week 1, 1900).  For week 1 of any year, the previous week is always week
       * 53, but week 53 may not contain any days (you should check for this).
       *
       * @return The preceding week (possibly <code>null</code>).
       */
      @Override
      public RegularTimePeriod previous() {
  
          Week result;
          if (this.week != FIRST_WEEK_IN_YEAR) {
              result = new Week(this.week - 1, this.year);
          }
          else {
              // we need to work out if the previous year has 52 or 53 weeks...
              if (this.year > 1900) {
                  int yy = this.year - 1;
                  Calendar prevYearCalendar = Calendar.getInstance();
                  prevYearCalendar.set(yy, Calendar.DECEMBER, 31);
                  result = new Week(prevYearCalendar.getActualMaximum(
                          Calendar.WEEK_OF_YEAR), yy);
              }
              else {
                  result = null;
              }
          }
          return result;
  
      }
  
      /**
       * Returns the week following this one.  This method will return
       * <code>null</code> for some upper limit on the range of weeks (currently
       * week 53, 9999).  For week 52 of any year, the following week is always
       * week 53, but week 53 may not contain any days (you should check for
       * this).
       *
       * @return The following week (possibly <code>null</code>).
       */
      @Override
      public RegularTimePeriod next() {
  
          Week result;
          if (this.week < 52) {
              result = new Week(this.week + 1, this.year);
          }
          else {
              Calendar calendar = Calendar.getInstance();
              calendar.set(this.year, Calendar.DECEMBER, 31);
              int actualMaxWeek
                  = calendar.getActualMaximum(Calendar.WEEK_OF_YEAR);
              if (this.week < actualMaxWeek) {
                  result = new Week(this.week + 1, this.year);
              }
              else {
                  if (this.year < 9999) {
                      result = new Week(FIRST_WEEK_IN_YEAR, this.year + 1);
                  }
                  else {
                      result = null;
                  }
              }
          }
          return result;
  
      }
  
      /**
       * Returns a serial index number for the week.
       *
       * @return The serial index number.
       */
      @Override
      public long getSerialIndex() {
          return this.year * 53L + this.week;
      }
  
      /**
       * Returns the first millisecond of the week, evaluated using the supplied
       * calendar (which determines the time zone).
       *
       * @param calendar  the calendar (<code>null</code> not permitted).
       *
       * @return The first millisecond of the week.
       *
       * @throws NullPointerException if <code>calendar</code> is
       *     <code>null</code>.
       */
      @Override
      public long getFirstMillisecond(Calendar calendar) {
          Calendar c = (Calendar) calendar.clone();
          c.clear();
          c.set(Calendar.YEAR, this.year);
          c.set(Calendar.WEEK_OF_YEAR, this.week);
          c.set(Calendar.DAY_OF_WEEK, c.getFirstDayOfWeek());
          c.set(Calendar.HOUR, 0);
          c.set(Calendar.MINUTE, 0);
          c.set(Calendar.SECOND, 0);
          c.set(Calendar.MILLISECOND, 0);
          return c.getTimeInMillis();
      }
  
      /**
       * Returns the last millisecond of the week, evaluated using the supplied
       * calendar (which determines the time zone).
       *
       * @param calendar  the calendar (<code>null</code> not permitted).
       *
       * @return The last millisecond of the week.
       *
       * @throws NullPointerException if <code>calendar</code> is
       *     <code>null</code>.
       */
      @Override
      public long getLastMillisecond(Calendar calendar) {
          Calendar c = (Calendar) calendar.clone();
          c.clear();
          c.set(Calendar.YEAR, this.year);
          c.set(Calendar.WEEK_OF_YEAR, this.week + 1);
          c.set(Calendar.DAY_OF_WEEK, c.getFirstDayOfWeek());
          c.set(Calendar.HOUR, 0);
          c.set(Calendar.MINUTE, 0);
          c.set(Calendar.SECOND, 0);
          c.set(Calendar.MILLISECOND, 0);
          return c.getTimeInMillis() - 1;
      }
  
      /**
       * Returns a string representing the week (e.g. "Week 9, 2002").
       *
       * TODO: look at internationalisation.
       *
       * @return A string representing the week.
       */
      @Override
      public String toString() {
          return "Week " + this.week + ", " + this.year;
      }
  
      /**
       * Tests the equality of this Week object to an arbitrary object.  Returns
       * true if the target is a Week instance representing the same week as this
       * object.  In all other cases, returns false.
       *
       * @param obj  the object (<code>null</code> permitted).
       *
       * @return <code>true</code> if week and year of this and object are the
       *         same.
       */
      @Override
      public boolean equals(Object obj) {
  
          if (obj == this) {
              return true;
          }
          if (!(obj instanceof Week)) {
              return false;
          }
          Week that = (Week) obj;
          if (this.week != that.week) {
              return false;
          }
          if (this.year != that.year) {
              return false;
          }
          return true;
  
      }
  
      /**
       * Returns a hash code for this object instance.  The approach described by
       * Joshua Bloch in "Effective Java" has been used here:
       * <p>
       * <code>http://developer.java.sun.com/developer/Books/effectivejava
       * /Chapter3.pdf</code>
       *
       * @return A hash code.
       */
      @Override
      public int hashCode() {
          int result = 17;
          result = 37 * result + this.week;
          result = 37 * result + this.year;
          return result;
      }
  
      /**
       * Returns an integer indicating the order of this Week object relative to
       * the specified object:
       *
       * negative == before, zero == same, positive == after.
       *
       * @param o1  the object to compare.
       *
       * @return negative == before, zero == same, positive == after.
       */
      @Override
      public int compareTo(TimePeriod o1) {
  
          int result;
  
          // CASE 1 : Comparing to another Week object
          // --------------------------------------------
          if (o1 instanceof Week) {
              Week w = (Week) o1;
              result = this.year - w.getYear().getYear();
              if (result == 0) {
                  result = this.week - w.getWeek();
              }
          }
  
          // CASE 2 : Comparing to another TimePeriod object
          // -----------------------------------------------
          else {
              // more difficult case - evaluate later...
              result = 0;
          }
  
          return result;
  
      }
  
      /**
       * Parses the string argument as a week.
       * <P>
       * This method is required to accept the format "YYYY-Wnn".  It will also
       * accept "Wnn-YYYY". Anything else, at the moment, is a bonus.
       *
       * @param s  string to parse.
       *
       * @return <code>null</code> if the string is not parseable, the week
       *         otherwise.
       */
      public static Week parseWeek(String s) {
  
          Week result = null;
          if (s != null) {
  
              // trim whitespace from either end of the string
              s = s.trim();
  
              int i = Week.findSeparator(s);
              if (i != -1) {
                  String s1 = s.substring(0, i).trim();
                  String s2 = s.substring(i + 1, s.length()).trim();
  
                  Year y = Week.evaluateAsYear(s1);
                  int w;
                  if (y != null) {
                      w = Week.stringToWeek(s2);
                      if (w == -1) {
                          throw new TimePeriodFormatException(
                                  "Can't evaluate the week.");
                      }
                      result = new Week(w, y);
                  }
                  else {
                      y = Week.evaluateAsYear(s2);
                      if (y != null) {
                          w = Week.stringToWeek(s1);
                          if (w == -1) {
                              throw new TimePeriodFormatException(
                                      "Can't evaluate the week.");
                          }
                          result = new Week(w, y);
                      }
                      else {
                          throw new TimePeriodFormatException(
                                  "Can't evaluate the year.");
                      }
                  }
  
              }
              else {
                  throw new TimePeriodFormatException(
                          "Could not find separator.");
              }
  
          }
          return result;
  
      }
  
      /**
       * Finds the first occurrence of ' ', '-', ',' or '.'
       *
       * @param s  the string to parse.
       *
       * @return <code>-1</code> if none of the characters was found, the
       *      index of the first occurrence otherwise.
       */
      private static int findSeparator(String s) {
  
          int result = s.indexOf('-');
          if (result == -1) {
              result = s.indexOf(',');
          }
          if (result == -1) {
              result = s.indexOf(' ');
          }
          if (result == -1) {
              result = s.indexOf('.');
          }
          return result;
      }
  
      /**
       * Creates a year from a string, or returns null (format exceptions
       * suppressed).
       *
       * @param s  string to parse.
       *
       * @return <code>null</code> if the string is not parseable, the year
       *         otherwise.
       */
      private static Year evaluateAsYear(String s) {
  
          Year result = null;
          try {
              result = Year.parseYear(s);
          }
          catch (TimePeriodFormatException e) {
              // suppress
          }
          return result;
  
      }
  
      /**
       * Converts a string to a week.
       *
       * @param s  the string to parse.
       * @return <code>-1</code> if the string does not contain a week number,
       *         the number of the week otherwise.
       */
      private static int stringToWeek(String s) {
  
          int result = -1;
          s = s.replace('W', ' ');
          s = s.trim();
          try {
              result = Integer.parseInt(s);
              if ((result < 1) || (result > LAST_WEEK_IN_YEAR)) {
                  result = -1;
              }
          }
          catch (NumberFormatException e) {
              // suppress
          }
          return result;
  
      }
  
  }
  